This study contributes to our long-term efforts toward understanding: * Mixed layer dynamics and lateral mixing in the upper ocean. * Processes that communicate atmospheric forcing to the ocean interior. Existing high resolution regional models typically resolve the mean vertical structure of the upper ocean boundary layer. Physically-based parameterizations of vertical fluxes make it possible to account for subgrid mixing at length scales smaller than the layer depth, but no specialized parameterization is used to represent the dynamics of horizontal mixing below the O(1)km - O(10)km resolution scale. We aim to determine the physical limitations of subgrid parameterization on these scales. This project will address the following questions: * What physics govern horizontal and vertical mixing in the presence of horizontal variability on the 1-10 km scale? * What is the relative importance of horizontal and vertical mixing in determining the structure of the boundary layer? * How well can existing parameterizations simulate vertical and horizontal mixing? * What physics should be included to improve parameterizations?